Photographic developing process and temperature regulation



Sept. 17, 1929. s. N. PIFER PHOTOGRAPHIC DEVELOPING PROCESS ANDTEMPERATURE REGULATION Filed Aug. 25. 1927 Patented Sept. 17, 1929UNITED STATES PATENT OFFICE GEORGE N. TIFER, OF CLEVELAND, OHIO,ASSIGNOR T AMERICAN PHOTOTURE COM- PANY, OF NEW YORK, N. Y., ACORPORATION OF DELAWARE PHOTOGRAPHIG DEVELOPING PROCESS AND TEMPERATUREREGULATION Application filed August 25, 1927. Serial No. 215,287.

This invention relates to certain improvements in photography and hasparticular reference to the development of an exposed sensitized surfaceand the regulation of the temperature of the developing solutions.

This invention is in part a division of and in part a continuation of myapplication Serial No. 758,989 filed December 31, 1924, for automaticphotographing machine.

In my prior application I have disclosed an automatic photographingmachine wherein an exposure is made on a sensitized strip for thenegative, and after the exposed surface is developed an exposure is madeon a sensitized element for a positive picture, and after development ofthe second exposed surface the positive picture is ejected from themachine.

For the development both of the negative and the positive, a methodisemployed which is both very effective and rapid in action, this methodinvolvin the directing of atomized developing, washing and fixingsolutions successively onto the exposed surface, the solutions being infinely divided form and being blown onto the surface being treated by astream of air. The advantages of this method of development will bepointed out in a detailed description.

The above, process, while disclosed in my prior application, is claimedherein, and to that extent this application is a divison of my priorapplication. I

I have found that the process of development, briefly explained above,not only is very satisfactory and rapid in action but it lends itself toa very eflective, inexpensive and easily applied method of temperaturecontrol and regulation of the developing solutions.

It is well known that in photographygenerally the temperature of thedeveloping s0- lutions should be tempered both in extreme ly hot andextremely cold weather,the solutions, of course, being cooled in warmweather andwarmed in cold weather. When the conditions are such thatthesolutions are exposed to the extremes of temperature, the tempering ofthe solutions is generally accomplished by applying a coollng or aheating medium to the solutions in bottles or other containers, butgenerally these are quite bulky, with a result that the temperatureregulation is not accomplished easily or inexpensively. I have foundthat the temperature of the solutions can be tempered and regulated to anicety very easily and cheaply by my process simply by warmin orcooling, as the case may be, the

,The single figure of the drawing illustr'ates conventionally ordiagrammatically my improved method in its different phases.

Referring now to the drawing, 10 represents a memberhaving a sensitizedsurface 11 exposed in any suitable manner, as in an automaticphotographing machine or otherwise, which surface may be on the elementused in the production of the negative or on the element used in theproduction of a positive picture. In carrying out my process, while itis not essential that'the solutions used be in four receptacles, Iprefer to use four receptacles 12, 13, 14 and 15 as it simplifies themovement of the plunger which is utilized in controlling the air whichatomizes the different solutions. In case four receptacles are employed,as indicated, they will be provided, respectively, with a washingsolution (water), a developing solution, a washing solution, and afixing solution. These receptacles, for convenience, may be in the formof bottles, the necks of which may be extended into funnel-like chambers16 connected by tubes 17 to chambers 18 in which the solution will standat the same level as in the funnels 16. From the chambers 18, tubes 19extend. to nozzles 20 arranged close together and in substantiallyparallel relation while held in a suitable support 21.

The air which is utilized in atomizing the solutions is supplied by asuitable motor driven pump or a fan which is usually of small size. Theoutlet side of the pump is connected by a tube or pipe 23 to a. chamber24 in which is slidable a plunger 25 and which is provided in thisinstance with four air nozzles 26, the ends of which are just above andare close to the ends of the solution nozzles 20.

The plunger 25, which may be actuated in an suitable manner, is hollowand it is provi ed on one side with an elongated slot 27 which at alltimes registers with the supply pipe 23. On the other side it isprovided with a discharge opening 28 which, when the plunger is movedendwise, is adapted to register successively with passageways extendingthrough the four air nozzles 26.

Normally the plunger is stationary and occupies a given position suchthat the discharge opening 28 is closed and out of registration'with thedifferent air nozzles 26. To bring about the development of a sensitizedsurface, the plunger 25 is given a stepby-step motion so as tosuccessively position the discharge opening 28 in registration with thepassageways extending through thefour air nozzles 26 and then it ismoved back to neutral position. The efiect of this is to atomize thesolutions and to first direct onto the exposed surface an atomizeddeveloping solution from receptacle 13, then an'atomized washingsolution from receptacle 14, then an atomized fixing solution fromreceptacle 15, and then again an atomized washing solution fromreceptacle 12. The first three movements of the plunger neecssary toaccomplish the above are in the same direction to ward the right, andthen the plunger is moved back toward the left to bring the opening intoregistration with the air nozzle over the left-hand or end nozzle 20connected to receptacle 12, after which the plunger is moved to neutralposition until needed'for the next developing operation. In this waythedifferent solutions in very finely divided form are successively blownonto the surface beingtreated.

When this process is employed in an automatic photographing machine asdisclosed in my prior application referred to, the .plunger 25 isaetuatedautomatically at the proper time in the complete cycle of stepsor operations necessary to produce the finished picture, and, of course,the plunger also has a predetermined dwell when the opening 28 isbrought into line with each of the different nozzles 26 to cause theatomized solution, whether it be a developing solution, a washingsolution, or a fixing solution, to be 'di' rected onto the surface forjust the desired length of time. Furthermore, as disclosed in my priorapplication, the exposure is made for the negative, then the negativeis. developed, then an exposure is made from the negative onto asensitized blank for the positive picture, and this is followed by adevelopment of the positive. This requires two sets of the nozzles 20and 26 and two of the plungers 25, but only one set of the solutionreceptacles and one air pump are needed for the two atomizing outfits.

The two receptacles for water are utilized for convenience merelybecause it simplifies the movements to be given to the plunger. Ifdesired, one bottle or receptacle may be em ployed for the water whichis utilized for the wash after both the atomized developing and fixingsolutions have been applied.

This method of development is particularly efficacious inasmuch as thesolutions are rapidly and automatically carried awayfrom the surface bythe air stream blown thereon and, furthermore, the action of thesolutions is greatly accelerated by reason of the fact that they areatomized, which is responsible for a much quicker chemical action oroxidation than with the immersion process. further advantage in the useof this process is the fact that the solutions can be localized ordirected onto only that part of the surface which is to be treated. Thisenables the use of cards or other blanks containing a sensitized portionplaced or located in any desired .position and covering any desiredportion. However, the chief advantage is the fact that the entiredeveloping operation can be carried out quickly and effectively by theenhanced oxidizing action due to the atomized condition of thesolutions.

Considering next the second feature of the invention, i. e., thetemperature control or regulation, to accomplish this result, it is onlynecessary for me to regulate the temperature of the air which issupplied for atomizing the solutions and this can be done mostefficiently by heating or cooling the air as it passes through pipe 23between the air pump 22 and the chamber 24. This can be accomplished innumerous ways but in this instance a portion 23 of the tube or pipe 23is extended into. a chamber 29 adapted to con tain water which can becooled by ice or other refrigeration means and which can be heated inany suitable manner as by extending into the chamber in contact with thewater an electrical heating element 30. In this manner, in cold Weatherthe air which" is utilized in atomizing the solutions employed indeveloping the surface may be warmed and in hot weather it may becooled. In either case, the solutions themselves are warmed or cooledand the development will take place 'under temperature conditions whichwill produce the best results. It is, therefore, unnecessary to attemptto apply the heating or cooling medium direct to the solutions, as, forexample, in the containers 12 to 15.

While I prefer to regulate the temperature at which the developing isaccomplished by warming or cooling the air as it passes from the pump 22to the nozzles, still this is'not essential as the air may be warmed orcooled before it is supplied to the pump. In the event that the airiswarmed or cooled while passing from the pump to the nozzles, it is, of

course, unnecessary to employ a receptacle such as shown at 29, andother ways of heating or cooling the air may be employed, as, forexample, by surrounding suitable portions .of the tube or pipe betweenthe pump and the nozzles with a heating coil and with a refrigeratingor'cooling coil.- I, therefore, aim in my claims to cover allmodifications which do not involve a departure from the spirit and scopeof my invention. 7

Having thus described my invention, I claim: I

1. The process of developing an exposed photographic surface whichcomprises dlrecting onto the surface an atomized developing solution.

2. The process of developing an exposed photographic surface whichcomprises directing onto the ex osed surface a stream of air containinga ely divided developing solution.

3; The process of developing an exposed photographic surface whichcomprises directture has been raised or lowered as the case may be.

8. The method of developing a photographic surface with temperatureregulation which comprises directing atomized solutions onto the exposedsurface with an air streamand either cooling the air stream if thetemperature is high or warmingthe air stream if the temperature is low.

In testimony whereof, I hereunto aflix my signature.

GEORGE N. PIFER.

ing successively onto the exposed surface ato mized developing, washingand fixing solutions. p

4. The process of developing an exposed photographic surface which,comprises directing onto the exposed surface a stream of air containingfinely divided developing, washing and fixing solutions which areapplied successively. a

5. The process of developing an exposed photographic surface whichcomprises directing an atomized developing solution onto the surface andregulating the temperature of the atomizing medium to bring about thedevelopment at the desiredtemperature.

6. The method of regulating the temperature at which a photographicsurface is de-' veloped which comprises blowing a finely 'di-.

vided developing solution onto the surface with a stream of air whosetemperature has been regulated. 7,. The method. of regulating thetemperature at which a photographic surface is de-

